The present invention supports an optical encoder attached to the shaft of a rotor of an electric motor; and, more specifically, the present invention relates to an apparatus for attachment of an optical encoder after centrally locating the optical encoder over the central axis of the electric motor rotor and affixing the encoder to the rotor to more precisely measure speed on the rotor for control purposes.
Previous attempts to measure rotation of a rotor often involved attaching on the motor assembly and attaching a shaft from the motor to the encoder leaving an opening and permitting the encoder to turn with the natural torque produced by the rotor. The present invention circumvents that issue by allowing the encoder to be safely attached to the shaft of the rotor ensuring consistent and accurate measurement of the rotational speed of the rotor and sealing the bearing from intrusion of dirt and contaminants from the rig floor. The speed measurement is thus increased in accuracy and both the encoder and the drilling motor remain sealed from contamination.